2012 Mercury 60hp EFI blows 15 amp fuse for no apparent reason

[caveman52]

I have a 2012 Mercury EFI 60 hp motor that came on my Tracker 175, which I bought new. In the second year of use (after the warrantee was expired, of course!), while pulling my kids on a tow-able, I shut the motor off to collect a kid from the water and when I went to crank the motor, ALL of the electronics were dead. Eventually we found a 15 amp fuse blown in the motor. I replaced it and everything went back to running. That same fuse has blown several times in the last 2 years. Each time I replace it and off we go. Each time, everthing is working fine, I turn off the motor and when I try to turn it back on....NOTHING! Last night, It blew 3 times in a row in my driveway, just trying to turn on the ignition switch to check the gas gauge. I never touched the throttle or even moved the motor! Does anyone have any idea what could be causing this or where I should look to begin tracking this thing down. I know Bass Prod Shops is going to charge me an arm & leg to find it. Thanks for your help!

 

[Fun Times]

Hi there, welcome to iboats!

One step you might want try doing is contacting Mercury marine customer assistance with your engine serial number to see if by chance that there's any known service bulletins covering blown fuses. Either call or email. https://www.mercurymarine.com/en/us/contact/outboard-customer-assistance

Are you able to tell what the fuse is for? Main power relay, SmartCraft data bus, fuel pump/IAC/Fuel Injectors, or Ignition coil?

Post your engine serial number if you'd like to find a service manual part number for your engine model.

 

[caveman52]

The fuse seems to control all of the electronics on the dash board AND the switch that raise & lowers the motor. Thanks for the tip on Cust serv for Mercury. I will do that.

 

[gm280]

Does any of the wires or connections look corroded? Corrosion will cause a higher current draw tripping circuit breakers and blowing fuses that are close to their rating.

 

[caveman52]

No, the boat and motor are relatively brand new, as far as use goes. The motor is spotless under the cover. I have not come across any corrosion yet

 

[Fun Times]

You'll need to check your service or owners manual or maybe fuse box cover/connector holder to confirm this but I believe there should be three 20 amp fuses and one 15 amp fuse in there. The 15 should be for the smartcraft data, all the others should be for the ignition, fuel pump, main relay, etc. using a 20 amp.

If you're using a 15 in a 20 amp circuit then it could blow.

It's been awhile since I've seen the later bulletins but I think (not positive) merc knows about this one.

 

[caveman52]

As I suspected, Mercury Marine just said take it to your dealer. There thought is it might be a faulty ignition switch. Seems like if it was the ignition switch, it would do it every time.

 

[Alanwray]

What did you find causing this issue? I’ve tried everything I know and still have the same 15a fuse blowing. Always does it intermittently and can never get it pin pointed. Any help is appreciated